Air release valve



y 1932- s. F. HITCHCOCK ,856,914

AIR RELEASE VALVE Filed Aug. 20, 1928 iii? 1 A l! GUY I. HITCHCOOK, OF HOUSTON, TEXAS,

Patented May 3, 1932 PATENT OFFICE ASSIGNOR OF ONE-THIRD T'O THOMAS H.

MEEKS AND ONE-THIRD T J OE L. TOMLINSON, BOTH 0F HARRIS COUNTY, TEXAS AIR RELEASE VALVE Application filed August 20, 1928. Serial No. 300,705

This invention relates to new and useful improvements in an air release valve.

One object of the invention is to provide novel type of release valve, adapted to be L] applied directly to an air pressure reservoir or the extension pipe lea-ding therefrom forming part of the air brake system of railway trains and whereby the air pressure may be easily relieved from said reservoir.

Another object of the invention is to pro-' vide an air release valve of the character described which, when opened, will remain open until the air pressure in the reservoir voir, or line, of an air brake system, and

which will automatically release an overcharge of air pressure and after such release will automatically close. 7 V

A further feature of the invention is to provide an air release valve which may be operated from either side of a railway car, which is of very simple construction and may be easily operated and readily applied.

WVith the above and other objects in'view this invention has particular relation to certain novel features of construction, operation and arrangement of parts, an example of which is given in this specification andillustrated in the accompanying drawings where- Figure 1 shows a vertical sectional view of the valve applied to an air pressure res-c ervoir, and

Figure 2 shows a plan .view thereof.

Referring now more particularly to the drawings wherein like numerals of reference designate similar parts in each of the figures the numeral 1 designates the air pressure reservoir or cylinder usually carried beneath the'railway car. There is a valve body 2 whose lower end 3 is reduced and outwardly threaded and thus adapted to be screwed into a tapped hole in the reservoir, or an air line connected therewith. Above the reduced end .3 the body is square or hexinto a cylinder 5, having a lateral relief port 4 6. An air relief conduit 7 leads up through the body 2 from the interior of the reservoir and terminates in the cylinder 5. Driven into the upper end of this relief conduit there is a tubular valve seat 8 and a valve 9 cooperates with said seat to normally close the relief conduit.

There is a plunger 10 which works in the cylinder 5 and which is formed with an upstanding sleeve like bearing 11 through which the'upstanding valve'stem 12 works. The lower end of this stem carries the valve 9 and is enlarged and'normally seated in the central recess 18 in the underside of the plunger 10. The upper end of the stem 12 Works through a central bearing 14 in the cap 15, This cap is bolted onto the body 2 and encloses a coil spring 16 which surrounds the bearing 11 and is interposed between the cap and plunger and normally holds the valve 9 in closed position, also holdin'gthe plunger 10 in position to close the port 6.

Fixed on the stem 12 and spaced beneath the upper end of the cap 15 there is an annular stop 17 and interposed between this stop and the bearing 11 there is a light coil spring 18.

on opposite sides of the upper end of the stem 12 are the valve operating levers 19, 19.

These levers are pivoted at one end between the respective ears 20, 20 upstanding from the cap'15 and disposed on opposite sides of the stem, 12.

The free ends of these levers are disposed in opposite directions and are downwardly curved and their other ends are connected to the inner ends of the operating rods 21, 21. The outer ends of these rods are accessible under the respective sides of the car beneath which the reservoir is located.

The upper end of the stem 12 carries'the oppositely disposed studs 22, 22 which work through bearings in the respective levers l9.

Normally, the air pressure in the reservoir will not be suflicient to lift the valve 9 and the plunger 10 on account of the small area of the valve 9 against which the pressure may operate. In order to relieve the pressure in the reservoir either rod 21 may be pulled outwardly which will operate to elevate the free end of the corresponding lei er 19 and the plunger 10 will thereby be slightly lifted to admit air into the cylinder 5 and on account of the large plunger area against which the air, under pressure may operate, the plunger will be lifted by said pressure to uncover the port 6 and the pressure in the reservoir will thereupon be reduced to such a point that the air brakes will be released. Thereupon the spring 16 will force the plunger 10 and valve 9, downwardly and close the port 6 and the relief conduit 7. If it be desired, at any time, to close the conduit 7, before the plunger descends, to cut off the airfrem the cylinder 5 either rod 21 may be forced inwardly and this will operate to seat the valve 9 in advance of the descent of the plunger 10. v

a In case of overcharge, say aboveone hundred twenty pounds, in the-cylinder 1 the pressure of the spring 16 will be overcome and the valve 9 and plunger 10 will be forced open and will release the air pressure in said reservoir andreduce the pressure to about 30 pounds and thereupon the spring 16 will cause the valve 9 to close and the cylinder 10 to return to original position. When valve 9 is opened were it not held firmly seated in the recess 13, airwould passup through the bearing 11 around the rod 12 to equalize pressure on both sides. 7 I

As the plunger 10 moves downwardly the air in the cylinder will be forced out through the relief port 23 which port also prevents the accumulationof air in the cylinder which might leak past the seat 9 and prematurely lift theplunger 10 and release the air pres sure in the reservoir. I While I have shown what I now consider to be the preferred form of the invention it is obvious that mechanical changes maybe made therein and equivalents substitutedfor the parts shown and I reserve the rightto make such changes as may be found desirable within the principle of the invention.

lVhat I claim is 7 I v I 1. A valve including a valve body formed with a cylinder for containing fiuid under pressure and having a relief conduit entering the cylinder and a relief port leading therefrom, a plunger in the cylinder normally closing said port,a valve associated with the plunger and independently movable relative thereto, and normally closing said conduit, means normally over coming said pressure and holding said plunger and valve in closed position, oppositely disposed levers operatively connected to the valve, through either of which the valve and plunger may be moved to open said conduit and port.

2. A valve including a valve body formed with a cylinder for pressure fluid and having an air inlet conduit and a relief port, a plunger in the cylinder arranged tonormally close said port, a yieldably mounted valve arranged to normally close said conduit, a yieldable member operating against the plunger, and adapted to over come said pressure and hold the valve and plunger in their said normal positions, a pair of levers operativel'y' connected with the valve through either of which the valve and plunger may be moved to open said conduit and port.

3. A valve including a valve body formed with a cylinder and having a pressure relief conduit entering the "eylinder and a pressure relief port leading from the cylinder, a cap fastened to said body and having a bearing, a plunger in the cylinder adapted to close said port, said plunger having an axial bearing, a valve stein working through said bearings whose lowerend is provided with a valv'e adapted to 'c'lose said conduit, a yieldable member interposed between the cap and plunger, a yieldable member on which said stem is supported, levers pivoted to said cap and operatively connected to 'said stem.

4, A valve including a valve body formed with a cylinder having an air relief conduit enteringthe cylinder and an air relief port leading from the cylinder, a plunger in the cylinder normally blockin said port, said plunger having an axial caring, a valve stem working through said bearing, a valve carried by the stem which normally closes said relief conduit, a cap on said body formed with a bearing through which the said stem works, a yieldable member operating against the plunger and normally holding the plunger and valve in position to close saidport and conduit and means connected to the stem through which the plunger and valve may be moved to open said conduit and ort.

5. A valve including a valve b0 y formed with a cylinder and havingan inlet conduit, a valve seat in the end ofsaid conduit which terminates in the cylinder, said' cylinder also having a relief port,,a plunger injsaid cylinder normally blocking said relief port, a yieldably supported valve associated with the plunger and adapted to cooperate wit said seat, cap secured to said body and formed with a bearinga stem attached to said valve and working through said bearing, a .yield'able member interpos'edb'etween the cap and plunger, a lever having a pivotal connectionwith the outer entl of said stein, one end of said lever being pivoted to sai'd tap, an operating rod connected to the ea-reread of said lever.

I 6. A valvenrechani sm including abtdy, formed with the cylinder havin a pressure release conduit and an air relief porn-a plunger in the cylinder'normally'blecking said port, a valve which normally blocks said c'on'duit,'a cap on said body andhaving a bearing, a stem on the valve and worln'ng through said bearing and operatively connected with, and movable independently of, the plunger, a pair of levers on the cap and operatively connected with said stem, operating rods connected to said levers and a yieldable member acting against the plunger and normally holding the plunger and valve in position to close said port and conduit respectively.

7 A valve mechanism including a body having a bearing and formed with a cylinder and having a pressure relief conduit and an air relief port, a plunger in the cylinder normally blocking said port and having an axial bearing, a stem, a valve on said stem, which controls said conduit said stem working through said bearings, a yieldable seat on the stem against which the plunger is seated, a lever connected to the outer end of said stem, an operating rod connected to the lever and a yieldable member operating against the plunger and normally holding said plunger and valve in position to close said port and conduit respectively.

8. A valve including a body having a cylinder and provided with a relief conduit entering the cylinder and a relief port leading therefrom, a plunger in the cylinder normally closing said port, a valve associated with the plunger and normally closing said conduit, means normally holding said plunger and valve in position to close said port and conduit respectively, means for manually actuating the valve and plunger into open positions, said actuating means being efi'ective to move said valve, independent of the plunger, to close said conduit in advance of the closing of the port by said plunger.

In testimony whereof I have signed my name to this specification.

GUY F. HITCHCOCK. 

